Bending device



Mar h 10, 1964 J. R. WILLIAMS ETAL 3, 4, 9

w Z, I

INVENTORS. JACK R. MLLIAMS BY CLARENCE L.FLssAT March 10, 1964 J. R.WILLIAMS ETAL 3,124,192

BENDING DEVICE Filed March 28, 1960 2 Sheets-Sheet 2 JNVENTORS. JACK R.MLLIAMS BY CLARENCE L. FLESSATE MMp-ZW Wfiorn eys United States PatentOfi 3,124,192 Patented Mar. 10, 1964 iice 3,124,192 SENDING DEVI CE JackR. Wiliiams, Painesviiie, Ohio, and Ciarence L. Fiessate, Wauhesha, Wis,assignors to Appiied Power Industries, Inc, a corporation of WisconsinFiied Mar. 28, 1969, Ser. N 17,882 4 Ciaims. Ci. 153-38) The presentinvention relates generally to improvements in the art of bendingelongated metal bar or plate stock, and relates more particularly toimprovements in the construction and operation of portable poweractuated bending devices adapted to bend fiat bars, such as bus bars,either in a direction extending across the width or in a directionextending across the depth of the bar.

A primary object of this invention is to provide improvements in bendingapparatus or" the type generally shown and described in US. Patent No.2,255,985, dated September 16, 1941 to E. M. Pfauser, which enables suchdevices to be used in bending plate stock.

As shown in Patent No. 2,255,985, it has heretofore been proposed toprovide portable assemblages for bending pipe or tubing comprising, ingeneral, a pair of spaced triangular plates secured at a common apex tothe end of a power cylinder and having reaction blocks pivotally mountedtherebetween near the other apices thereof, and an arcuate shoeattachable to the power ram or plunger for movement therewithintermediate the plates and between the reaction blocks to bend the pipeor tube upon application of pressure to the ram.

While such prior bending devices have enjoyed widespread acceptance andhave proven highly successful and efficient in operation, their use hasthus far been limited to bending operations on elongated cylindricalstock such as pipe or tubing. heretofore performed wtih such apparatushas been restricted to arcuate formations as distinguished from sharpangular bends.

In working with plate or flat bar stock such as bus bars, it isfrequently desired to effect sharp angular bends in a direction acrossthe width or thickness of the bar, herein referred to as flat bends, andit is also often desired to bend the flat bar stock in the direction ofthe depth of the bar, herein referred to as edge bends. While variousdevices have heretofore been provided which enable flat bending of thestock, there are no known available devices of a portable nature bymeans of which edge bending may be satisfactorily accomplished, and ithas therefore been common practice to either out two bars to size andthen lap and bolt the same together or to diagonally cut the bar stockand unite the same by miter joints to obtain the desired curvature.

It is there-fore an object of this invention to provide a portablebending assemblage which is readily adapted for use on flat bar stock ofdifferent dimensions and by means of which either fiat or edge bends maybe effected.

Another object of the invention is to provide an improved bending devicewhich may be quickly and easily converted either for use in forming fiatbends or for the formation of edge bends on flat bar or plate stock.

Still another object of the invention is to provide an improved portablebender by means of which diverse arcuate as well as sharp angular bendsmay be imparted to flat bar stock without lateral distortion of thestock.

These and other specific objects and advantages of the invention willbecome apparent from the following detailed description.

A clear conception of the features constituting the presentimprovements, and of the construction and operation of a typical bendingassemblage for operating on bar Moreover, the type of bends 3 stock andembodying the invention, may be had by referring to the drawingsaccompanying and forming a part or" this specification in which likereference characters designate the same or similar parts in the severalviews.

FIG. 1 is a part sectional plan view of a typical fluid pressureactuated bending device embodying the invention and showing a fragmentof flat bar stock positioned between the bending shoe and reactionblocks just prior to performing an edge bend thereon, the side plate ofthe bending shoe being removed and parts being broken away for the sakeof clarity;

FIG. 2 is a similar part sectional view of the bender but showing thepower ram and bending shoe extended to a position wherein the edgebending operation on the bar stock is completed, parts again beingbroken away for clarity;

PEG. 3 is an exploded and somewhat enlarged perspective view or" one ofthe improved bendin shoes for per forming edge bends on fiat stock;

FIG. 4 is a similarly enlarged part sectional side view of the assembledbending shoe of FIG. 3, the bar stock to be bent being shown by means ofdot-and-dash lines;

FIG. 5 is another pian View of the bending device of FIG. 1 but showingthe same performing a iiat bend on a fragment of bar stock with a fiatbending shoe mounted on the ram and a fiat bending die secured to thebender frame, a part of the bending die frame being broken away for thesake of clarity;

FIG. 6 is a perspective view of the bending shoe for performing flatbends as shown in FIG. 5; and

FIG. 7 is a perspective view of the bending die used in flat bendingoperations.

White the invention has been shown and described herein as applied to afluid pressure actuated portable bending assemblage of the typegenerally disclosed in US. Patent No. 2,255,985 and as beingparticularly useful in operating on bus bar stock, it is not intended tothereby unnecessarily restrict the application or use of theimprovements; and it is furthermore contemplated that specificdescriptive terms employed herein shall be given the broadest possibleinterpretation consistent with the disclosure.

Referring to the drawings, the portable bending device shown thereincomprises, in general, a power ram having a fluid pressure actuatedplunger 10 movable within a cylinder 11; a frame formed by a pair ofparallel rigid side plates 12, 13 each having its mid-portion detachablybut firmly secured to the open end of the cylinder 11 and also havingtherein at least two series of axially alined holes 14, 15 respectivelydiverging away from the cylinder end along each side thereof; a workreceiving bending shoe indicated generally at 16 and which will behereinafter described in detail detachably secured to the extreme outerend of the plunger 10 for movement thereby between the spaced plates 12,13 and intermediate the oppositely diverging sets or series of holes 14,15; and a pair of work engaging reaction blocks 17 pivotally cooperablewith selected pairs of alined holes 14, 15 on opposite sides of theplunger 11 for cooperation with the plunger and the shoe 16 to effectbending of a piece of elongated bar stock 18 positioned against theblock 17.

The mid portion or apex of at least one of the triangular plates 12, 13may be detachably secured to the open end of the plunger guidingcylinder 11 as by means of a removable spacing and clamping bracket 21?,and the ram assemblage may be of any well known type operable as byfluid pressure supplied from a suitable pump (not shown) through aflexible conduit 21. The shoe 16 may be detachably secured to the end ofthe plunger 1% in any suitable manner as by means of a traverse pin 22cooperable with an annular recess 23 formed on the plunger, and theassemblage may thus be conveniently assembled and dismantled forplacement and removal of the work pieces 18 and for interchanging theshoes 16. Each of the reaction blocks 17 is of polygonal shape havingrelatively deep rectilinear work receiving grooves 24 about theperipheries thereof, and these blocks 17 are rotatably mounted uponremovable pivot pins adapted to coact with selected matching sets ofholes 14, 15 in the plates 12, 13.

The general assemblage thus described is well known as shown in US.Patent No. 2,255,985, and such apparatus has enjoyed considerablesuccess. However, the utility thereof has heretofore been undesirablyrestricted to bending operations on pipe or tubing, and by reason of thepresent invention, this type of portable bending apparatus may now bereadily adapted for bending flat bar stock either in a direction lyingin the plane of the width or transversely across the width thereof.

In addition to modifying the reaction blocks 17 to provide rectilinearwork receiving grooves 24- for proper seating of the fiat work 18, thepresent invention contemplates provision of a special unique workbending shoe 1% for edge bending operations. The improved shoecomprises, a pair of spaced side plates 27, 28 and an intermediatebending plate 29, one of the side plates 27, 23 having a plungerreceiving socket 3t) rigidly secured thereto as by welding or the like.

The bending plate 29 has an outwardly presented bending surface 31engageable with one longitudinal edge of the work 18, the bendingsurface 31 being of any desired arcuate curvature or radius, and thewidth of the bending plate 29 selected is critical and should be from 4%to 10% larger than the thickness or width of the work 18 to be bent toallow the material to flow while still preventing lateral distortionthereof. While the curved segment or plate 29 performs the edge bendingoperation upon longitudinal movement of the plunger iii under pressureto move the bending shoe 16 between the reaction blocks 17 as shown inFIG. 2, the side plates 27, 28 provide lateral stability and to preventlateral distortion of the work 18 during the bending operation, the sideplates 27, 28 should be of considerably greater length or depth than thebending plate 29 as shown. The side plates 27, 28 and bending segment orplate 29 may be firmly secured together as a unit in any suitable manneras by capscrews 32 receivable in alined 33, and one or the other of theplates 27, 28 may be provided with positioning pins 34 cooperable withmatching holes 35 in the bending plate 29 to facilitate proper assembly.The bending shoe assembly 16 is secured to the plunger 10 as aforesaidby means of a traverse pin 22 cooperable with the groove 23 in theplunger, the pin 22 being receivable in a hole 36 formed in the socket30 of the shoe in a known manner.

While it is not desired to limit the invention to the exact constructionof the bending shoe assemblage thus described, formation of the same ofseparate detachable side plates 27, 28 and a separate bending segment orplate 29 permits ready interchangeability of these parts to accommodateWork of diverse shapes and sizes as well as to permit performance ofdifferent edge bending operations. As shown in FIGS. 3 and 4, the plate27 may be readily rigidly secured to or formed integral with the socket30 and is located to one side of the center of the socket 30 to therebyproperly center the bending segment or plate 29. Also, the rear of thebending plate 29 is formed with a central U-shaped recess 38 receivableby the socket 30 to properly seat the same and provide stability, andthe rear of the plate 28 is formed with a similar tJ-shaped recess 39for like purposes.

For the performance of flat bends, we have provided the attachment shownin FIGS. 5, 6 and 7. This attachment comprises a die 46 formed by a pairof similar spaced side plates 47, 48 shown as being of generally V-shape connected at their apex or outer medial portion by a forming orbending block 49 of the desired angular cross-section. The wings of thedie side plates 47, 48 are provided with holes 5t) alinable withselected ones of the sets of holes 14, 15 in the bender frame so as toremovably receive suitable T pins 51 or the like. Cooperable with thedie 46 is a bending shoe 52 having a socket 53 for receiving the end ofthe ram plunger 1%) and attachable thereto by means of the traverse pin22 as above described with reference to the attachment of the shoe 16.The shoe 52 has an angular working face 54- matching that of the dieblock 4).

When it is desired to form a flat bend on the bar stock 18, the edgebending shoe 16 is replaced in an obvious manner by the bending shoe 52,and the die 46 is secured to the side plates 12, 13 of the bender frameby means of the pins 51. With the plunger 16 backed up or retracted, thework to be bent is positioned against the die block 49, and pressure isthereafter applied by the ram plunger it? to form the desired flat bendas shown in FIG. 5, the plunger being retracted to its initial positionto re move the work.

From the foregoing detailed description, it is apparent that a bendingassemblage has been provided for working on flat bar stock which isextremely simple and economical in construction and which is moreoverhighly efficient in the performance of areuate edge bends as well asfiat angular bends. The side plate 13 of the main bender frame may bereadily removed for access to either the edge bending shoe 16 or theflat bending shoe 52, either of which may be readily removed for quickand easy replacement by the other. When the edge bender 16 is utilized,the reaction blocks 17 may be readily interchanged to accommodate theparticular work piece 13 which is desired to operate on, and the workpiece 13 may be readily positioned as shown in FIG. 1 by removthe sideplate 28 of the bending shoe, positioning the work piece and thenattaching the side plate 23 to locate the work 13 in the plane ofmovement of the bending plate 29. On the other hand, whenever it isdesired to perform fiat bending operations as shown in FIG. 5, it isonly necessary to replace the shoe 16 with the shoe 52 and to secure thedie 46 in position for the performance of the bending operation ashereinabove described.

It should be understood that it is not desired to limit this inventionto the exact details of construction or to the precise mode of operationof the bending apparatus herein shown and described, since variousmodifications within the scope of the appended claims may occur topersons skilled in the art to which this invention pertains.

We claim:

1. Apparatus for bending fiat bar stock to produce edge bends therein,said apparatus comprising, power means movable axially along a guidemember, at least one rigid plate secured to said guide member andextending in the direction of movement of said power means to provide aframe, a bending shoe movable axially by said power means relative tosaid frame, said bending shoe having a bending plate formed with aforwardly presented bending face and secured between side platesprojecting forwardly beyond said face to form an open receiving groovefor the edge of a bar to be bent, one of said side plates beingdetachable to permit free lateral access to said groove, and a groovedreaction block pivotally and removably mounted on said frame on eachside of the path of movement of said bending shoe.

2. Apparatus for bending flat bar stock to produce edge bends therein,said apparatus comprising, power means movable axially along a guidemember, at least one rigid plate secured to said guide member andextending in the direction of axial movement of said power means toprovide a frame, a bending shoe movable axially by said power meansrelative to said frame, said bending shoe having a bending plate formedwith a forwardly presented bending face and secured between side plateswhich project beyond said face to form a forwardly open receiving groovefor the edge of a bar to be bent, one of said side plates having meansfor detachably securing the same to said power means and said bendingplate and the other side plate being detachably secured to said one sideplate, and a grooved reaction block pivotally and removably mounted onsaid frame on each side of the path of movement of said bending shoe.

3. A bending shoe for use in producing edge bends in fiat bar stock,said bending shoe comprising, a bending plate interposed between a pairof side plates, said bending plate being formed with a forwardlypresented work engaging bending face and said side plates being ofgreater length than said bending plate so as to project forwardly beyondsaid bending face and form an open work receiving groove at its forwardend, means for detachably securing said side plates to said bendingplate to normally retain the same in assembled condition, and means onone of said side plates for attaching the same to a power actuator.

4. A bending shoe for use in producing edge bends in flat bar stock,said bending shoe comprising, a bending plate interposed between a pairof side plates, said bending plate being formed with a forwardlypresented work engaging bending face and said side plates being ofgreater length than said bending plate so as to project beyond saidbending face and form a forwardly open work receiving groove, means fordetachably securing said side plates to said bending plate to form aunitary assemblage, and a socket rigidly secured to the rear edge of oneof said side plates for attaching the same to a power actuator, saidbending plate and the other of said side plates each being formed with arearwardly open U-shaped recess receivable by said socket forpositioning and positively locating said plates thereon.

References Cited in the file of this patent UNITED STATES PATENTS924,514 Warehock June 8, 1909 1,002,329 Sprengle Sept. 5, 1911 1,054,132Miner Feb. 25, 1913 2,725,916 Gershater Dec. 6, 1955 2,808,095 Loughlinet al. Oct. 1, 1957 2,867,261 Traupmann Jan. 6, 1959 2,871,908 FlessateFeb. 3, 1959 2,882,952 Johnson Apr. 21, 1959 2,887,145 Tiedemann May 19,1959

1. APPARATUS FOR BENDING FLAT BAR STOCK TO PRODUCE EDGE BENDS THEREIN,SAID APPARATUS COMPRISING, POWER MEANS MOVABLE AXIALLY ALONG A GUIDEMEMBER, AT LEAST ONE RIGID PLATE SECURED TO SAID GUIDE MEMBER ANDEXTENDING IN THE DIRECTION OF MOVEMENT OF SAID POWER MEANS TO PROVIDE AFRAME, A BENDING SHOE MOVABLE AXIALLY BY SAID POWER MEANS RELATIVE TOSAID FRAME, SAID BENDING SHOE HAVING A BENDING PLATE FORMED WITH AFORWARDLY PRESENTED BENDING FACE AND SECURED BETWEEN SIDE PLATESPROJECTING FORWARDLY BEYOND SAID FACE TO FORM AN OPEN RECEIVING GROOVEFOR THE EDGE OF A BAR TO BE BENT, ONE OF SAID SIDE PLATES BEINGDETACHABLE TO PERMIT FREE LATERAL ACCESS TO SAID GROOVE, AND A GROOVEDREACTION BLOCK PIVOTALLY AND REMOVABLY MOUNTED ON SAID FRAME ON EACHSIDE OF THE PATH OF MOVEMENT OF SAID BENDING SHOE.